Abstract:
:Multichannel transmission has the potential to improve many aspects of MRI through a new paradigm in excitation. In this study, multichannel transmission is used to address the effects that variations in B(0) homogeneity have on fat-saturation preparation through the use of the frequency, phase, and amplitude degrees of freedom afforded by independent transmission channels. B(1) homogeneity is intrinsically included via use of coil sensitivities in calculations. A new method, parallel excitation for B-field insensitive fat-saturation preparation, can achieve fat saturation in 89% of voxels with M(z) ≤ 0.1 in the presence of ± 4 ppm B(0) variation, where traditional CHESS methods achieve only 40% in the same conditions. While there has been much progress to apply multichannel transmission at high field strengths, particular focus is given here to application of these methods at 1.5 T.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Heilman JA,Derakhshan JD,Riffe MJ,Gudino N,Tkach J,Flask CA,Duerk JL,Griswold MAdoi
10.1002/mrm.23238subject
Has Abstractpub_date
2012-08-01 00:00:00pages
631-8issue
2eissn
0740-3194issn
1522-2594journal_volume
68pub_type
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